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Updated: Jul 4, 2026
06:08
Design of Solid-State Fermentation Systems for Polymer Hydrolytic Extracellular Enzyme Production by Filamentous Fungi
Published on: June 6, 2025
Heat and mass transfer effects in static solid-substrate fermentations: design of fermentation chambers
1School of Chemical Engineering, Cornell University, Ithaca, New York 14853, USA.
Biotechnology and Bioengineering
|April 1, 1983
Summary
A new device enables simultaneous measurement of temperature and gas composition in solid-substrate fermentation. This research monitored tempeh fermentation, revealing steep temperature gradients and high carbon dioxide levels during mold growth.
Area of Science:
- Biotechnology
- Fermentation Science
- Process Engineering
Background:
- Solid-substrate fermentation is crucial for producing various food and industrial products.
- Monitoring internal conditions like temperature and gas composition is vital for optimizing fermentation processes.
- Existing methods often lack the capability for simultaneous, multi-point measurements within the fermentation bed.
Purpose of the Study:
- To develop and validate an experimental device for simultaneous, in-situ measurement of temperature and gas composition (O(2), CO(2)) at multiple depths within a solid-substrate fermentation bed.
- To characterize the dynamic changes in temperature and gas profiles during a specific solid-substrate fermentation process.
Main Methods:
- Construction of a novel experimental device capable of near-simultaneous measurements.
- Deployment of the device in a 6.35 cm deep fermentation bed.
- Time-dependent monitoring of temperature, mol % O(2), and mol % CO(2) at five distinct positions.
- Application of the device to a tempeh fermentation (Rhizopus oligosporus on soybeans).
Main Results:
- The device successfully provided simultaneous, time-dependent data on temperature and gas composition.
- Significant temperature gradients were observed, reaching up to 3°C/cm during active mold growth in tempeh fermentation.
- High concentrations of carbon dioxide (CO(2)) were detected, with levels reaching 21 vol. % in the bottom layer of the fermentation bed.
Conclusions:
- The developed experimental device is effective for characterizing internal micro-environmental conditions during solid-substrate fermentation.
- Understanding these gradients and gas dynamics is essential for controlling and optimizing fermentation processes like tempeh production.
- This technology offers a valuable tool for further research into microbial metabolism and process control in solid-state fermentations.
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